Mark w



(No Model.)

M. W. DEWEY. INGANDESCENT ELECTRIC LAMP.

No. 603,056. Patented Apr. 26, 1898.

w w E V w ATTORNEY UNITED STATES PATENT Orricn,

MARK W. DEWEY, OF SYRACUSE, NEW YORK, ASSIGNOR TO THE DEXVEY CORPORATION, OF SAME PLACE.

INCAN DESCENT ELECTRIC LAM P.

SZPECIFIGA'IION forming part of Letters Patent No. 603,056, dated April 26, 1898.

Application filed July 22, 1891.

To all whom it may concern.-

Be it known that I, MARK W. DEWEY, of Syracuse, in the county of Onondaga, in the State of New York, have invented new and useful Improvements in Incandescent Electric Lamps, (Case No. 99,) of which the following, taken in connection with the accompanying drawings, is a full, clear, and exact description.

My invention relates to the method of and apparatus for producing illumination in incandescent electric lamps and to electric resistances to be used in said lamps and in electric heaters; and it consists in the novel construction and arrangement of the filament or rings in such manner that said filament shall form a closed circuit.

The invention also consists in subjecting the closed filament to the inductive influence of the field produced by varying currents in an external electric conductor.

The principal object of the invention is to dispense with the usual electric conductors that lead in through the glass receiver, and this is accomplished by entirely or completely inclosing the light-giving conductor or filament with the glass receiver and arranging an electric conductor outside of the receiver and in inductive relation to the inclosed conductor. here the conductors are led in through the glass receiver, there is always more or less leakage, owing to the imperfect union of the materials, which expand differently from each other and are not elastic. By dispensing with the leading-in wires or conductors the receiver can be kept perfectly tight and an almost perfect and constant vacuum can be had to prevent the consumption of the carbon.

In the accompanying drawings, Figure 1 is a side elevation, partly in section, of an incandescent lamp embodying my invention; and Fig. 2, a front elevation of the same.

Referring specifically to the views, the numeral 1 indicates a filament or ring completely inclosed within a suitable glass receiver 2 of somewhat diiferent shape from those usually employed, the form shown in the drawings being preferred. The filament may be of any desired kind, being composed entirely or substantially of carbon and alone Serial No. 400,278. (No model.)

forms the secondary circuit within the receiver. The said filament is supported by projections 3 3, which extend from the inner surface of the back of the receiver. The receiver, by its back, is attached to a flanged shell or casing 4:, which is interiorly screwthreaded at its outer end to receive a screwthreaded base 5, which is provided with a central screw-threaded neck 6, adapted to be screwed into the usual bracket or holdersocket.

The numeral 7 indicates an outside coil situated within the casing 4:, having its supply-conductors 8 S passing through the neck 6 and through an aperture 9 in the base 5.

'The filament may be employed and inserted inthe primary coil 7, if desired, as shown in dotted lines 10 in Fig. 1. In this case, however, the casing 4 should be of non-conducting material, or so arranged in any suitable and well-known manner that an electric circuit will not be formed thereby.

It will be readily understood that the intensity of the glow of the lamp may be varied by separating the filament in the receiver or bulb from the primary coil 7, which is accomplished by unscrewing the glass receiver more or less from its base. i

The air is exhausted from the interior of the glass receiver in the usual and well-known manner. The filament constitutes a circuit closed upon itself and becomes the secondary coil of an induction coil or transformer when placed in suitable inductive proximity to the primary coil thereof, or, in other words, in the field of the transformer. hen the receiver 2 containing the filament is so placed in inductive proximity to a primary coil through which a varying (alternating or intermittent orpulsating) current of electricity is passing, then if the induced currents in the filament be of sufficient strength and pressure the said filament will glow or become incandescentand emit light in the ordinary way.

I do not wish to be understood as limiting myself to the precise construction of lamps herein shown and described, as various changes may be made within the scope of my invention without departing from its spirit or sacrificing the principle thereof.

What I claim is- 1. In an incandescent electric lamp, the combination of a light-giving electric conductor, a receiver made entirely of glass and completely inclosin g said conductor, and from which receiver the air is exhausted, and

an electric conductor outside of said receiverand in inductive relation to the inclosed conductor.

2. The combination of a carbon filament, with a receiver made entirely of glass and completely inclosing said filament, and from which receiver the air has been exhausted, and a coiled electric conductor outside of said receiver and in inductive relation to the inclosed filament.

3. The combination of a closed electric circuit formed substantially entirely of carbon, with a receiver made entirely of glass and inclosing said circuit, and from which receiver the air has been exhausted, and an electric conductor in inductive relation to said electric circuit for the purpose described.

4. The combination of a closed electric circuit made entirely or substantially entirely of carbon, with a receiver made entirely of glass and inclosing said circuit, and -from which receiver the air has been exhausted, and an electric conductor in inductive relation to the circuit or a portion thereof.

5. The method of causing incandescence in an electric glow-lamp, which consists in subjecting a ring or closed-coil filament inclosed in a substantially exhausted receiver to the inductive influence of the field produced by varying currents in an external electric conductor, substantially as described.

6. The method of causing incandescence in an electric glow-lamp, which consists in disposing the filament of said lamp as the secondary of an induction coil or transformer and causing a varying current to traverse the primary of said transformer, substantially as described.

7. The combination in an electric glow-lamp, of a filament in ring orclosed-coil form, and a means of producing a varying field of force; the said filament being located in said field and receiving a current by induction therefrom, substantially as described.

8. The combination of an electric glow-lamp having filament in ring or closed-coil form, a coil and a source of varying electric current connected with said coil; the said filament and said coil being disposed in inductive proximity, substantially as described.

9. The combination in an electric glow-lam p, of a receiver of translucent material and a filament without leading-in wires in the form of a ring or closed coil inclosed therein, substantially as described.

10. In an electric illuminating apparatus, a support, a means of producing a variable field of force combined therewith, a glowlamp receiver adapted to be held upon said support, and a filament in ring or closed-coil form inclosed within said receiver, the aforesaid parts being constructed and arranged so that when said receiver is held upon said support said filament shall be in said variable field, substantially as described.

11. In an electric illuminating apparatus, a primary coil, a glow-lamp receiver adapted to be supported thereon, and a filament in ring or closed-coil form inclosed within said receiver, the aforesaid parts being constructed and arranged so that when said receiver is supported on said primary coil, said filament shall become a secondary thereto and be caused to glow by the induced current, substantially as described.

12. In an electric illuminating apparatus, a primary coil, a glow-lamp receiver adapted to be supported thereon, a filament in ring or closed-coil form inclosed Within said receiver with reference to said primary coil: the aforesaid parts being constructed and arranged so that when said receiver is supported on said primary coil said filament shall become a secondary thereto and be caused to glow by the induced current, and also so that by the movement of said receiver as aforesaid said induction effect, and hence the intensity of the glow, may be varied, substantially as described.

13. In an incandescent lamp, the combination of a light-giving conductor, a suitable receiver completely inclosing said light-giving conductor, and from which receiver air is exhausted, and an electric conductor outside of said receiver and in inductive relation to the light-giving conductor.

In testimony whereof I have hereunto signed my name this 18th day of July, 1891.

MARK W. DEWEY. [L. s]

WVitnesses:

J. J. LAASS, H. M. SEAMANS. 

